Properties of Parallelograms

Front

What are the properties of a parallelogram?

Back

1. Opposite sides are congruent. 2. Opposite angles are congruent. 3. Consecutive angles are supplementary. 4. The diagonals bisect each other.

Front

What does it mean for opposite sides of a parallelogram to be congruent?

Back

It means that the lengths of the opposite sides are equal.

Front

If one angle of a parallelogram is 95°, what are the measures of the other angles?

Back

The opposite angle is also 95°, and the consecutive angles are 85° each.

Front

How do you find the measure of an angle in a parallelogram if you know one angle?

Back

Use the property that consecutive angles are supplementary. If one angle is x, then the adjacent angle is 180° - x.

Front

What is the sum of the interior angles of a parallelogram?

Back

360°.

Front

If the measure of angle R in a parallelogram is 40°, what is the measure of angle S?

Back

Angle S is 140° because opposite angles are congruent.

Front

What is the relationship between the diagonals of a parallelogram?

Back

The diagonals bisect each other.

Front

If x + 5 = 80 in a parallelogram, what is the value of x?

Back

x = 75.

Front

What is the definition of a parallelogram?

Back

A parallelogram is a quadrilateral with opposite sides that are parallel and equal in length.

Front

If one pair of opposite sides of a parallelogram is 10 cm and the other pair is 15 cm, what can be said about the sides?

Back

The opposite sides are congruent, so the sides are 10 cm and 15 cm each.